Okay I am looking to a put a new cam in my 1991 305TPI Z28. I want to keep it on budget becasue it would be temporary untill I have the money to build a 350. I have been looking at the lt1,zz4, and lt4 cams for the swap becasue they can be easily found cheap on ebay and other places. I researched and found these specs for the cams can soem please let me knwo that they are correct:

ZZ4:
208°/221° Duration @.050
.474/.510 valve lift
112° lobe separation angle

LT1:
201/207
.447/.459
115* LSA w/1.5 rockers

LT4:
203/210 Dur
.476/.480
Lift 115 LSA

Now my question which would work best for me? It is a daily driven street car, needs to pass emisions, and be extreamly friendly with my computer. I do have full exhaust, afpr, and when I do the cam I plan on doing as much porting as I can on my own. Thanks in advance.

 

Nice car. I like the zz4 the best, because of the higher amount of dur. The problem is that your stock heads won't flow enough air past .450" valve lift. I also think the 115 ls is a bit much, but it would be fine for a stock tpi setup, for the lowend. I think all cams would perform similarily, maybe a 5hp difference between them. I would say go with the lt-1 for your setup, it will probably give you about 15-20hp over your stock cam. You're not going to gain more than that from just a cam until you do heads and an intake, even though you have headers.

 

I was thinking the same. I am trying to get the 305 to hit 13.999 haha, just to prove all my buddies wrong that they cant be fast, before I finish the 350 build up...

With the lt1 cam am I going to need different rockers or pushrods?

 

What are your plans for the 350? I've built two now and I'm on my second 383. You'll be happy with the 350, but if there's anyway you could possibly get a stroker crank in that 350, then do it. There's no way to describe how much more fun that extra low end is with the extra stroke, even if you use the same 350 parts. Trust me with my exp.

 

the plans were for a mild street motor. 350, .30 over, forged pistons, vortec heads, lt4 hot cam, or the crane compucam, scoggin dickey lower intake, keeping tpi, 1.6 roller rockers... thats the plan I have in my head now... nothing to fancy, just soemthing that will run strong and fast.


but untill then I want the 305 to run a little faster.